The present invention generally relates to the mounting of a hard tonneau cover for pickup truck and more particularly pertains to the mechanism for hinging and securing such devices to the cargo box.
As more and more pickup trucks are being purchased and used as primary transportation, items often end up being carried in the cargo box that should more properly be secured from theft and protected from the elements. Tonneau covers, especially hard tonneau covers afford such protection and security and additionally enhance fuel mileage by smoothing out the air flow over the rear part of the vehicle. Additionally, many find an aesthetic appeal in covering up the cargo box of a pickup truck.
Hard tonneau covers are typically constructed of fiber reinforced resin, have a high quality finish to match the rest of the vehicle and form a weather tight seal about the top of the cargo box""s sidewalls when in the closed position. The covers are typically hinged at the front so as to allow the back to be pivoted upwardly and are latched and lockable at the rear. Telescoping gas struts are used to assist in lifting the cover and to then maintain it in its open position.
A difficulty associated with the adaptation of a hard tonneau cover to many truck applications is related to the hinging of the front end of the cover. While it is desirable to wrap the cover over the edges of the truck""s cargo box, including over the front rail, in order to provide a clean appearance and so as to hide unsightly hinging hardware while the cover is in its closed position, the typical close proximity of the front of the bed to the back of the truck cab is problematic as the cover is pivoted to its open position. This problem is further aggravated in some truck designs wherein the front edge of the truck""s cargo box has a non-square configuration that partially follows the contours of the back of the truck cab. While compound hinges can be configured to force the front edge of the cover to follow a complex path so as to clear the cab, the use of such hinges can compromise the ability to quickly and easily remove the cover from the truck when full access to the cargo bed is required such as when hauling oversized cargo. Compound hinges typically have multiple links as well as other hinge components that require partial disassembly in order to allow the cover to be detached.
An additional problem associated with many presently available hard tonneau cover devices is that the geometry of the gas strut mechanism that is used to assist in lifting the cover and propping it open is such that an insufficient amount of lifting force is available while the cover is in its closed position to unlatch the locking mechanism once it is unlocked. As a result, a rather cumbersome manipulation is required in an effort to simultaneously unlock the cover while attempting to grasp the rear edge of the cover to lift it. This is especially problematic in tonneau designs that wrap over the tailgate which avail only a very thin edge for grasping. The typical locking mechanism that is used in such applications precludes simply unlocking the cover and then using both hands to grasp and lift the edge of the cover as the weight of the cover will cause the cover to automatically relatch itself as soon as the lock is released.
It is therefore desirable to provide a tonneau cover hinging mechanism that forces the front edge of the cover to follow a complex path as it is opened so as to clear the back of the truck cab, yet allows the cover to be quickly and easily detached from the truck. Additionally, it is most desirable to provide a locking mechanism that allows the cover to be more easily opened.
The present invention provides a hard tonneau cover that is hinged near its front end by a compound hinge mechanism that controls the position of the front edge as the rear end of the cover is pivoted to its open position yet allows the cover to be quickly and easily removed. This allows the front edge of the cover to avoid interference with the truck cab despite a close proximity thereto even when the front edge is configured to partially wrap over the front top rail of the truck""s cargo bed. The cover is removable from the cargo bed without the use of tools and the hinge mechanism is completely hidden from view when the cover is in its closed position. Additionally, the cover is secured in its closed position by a locking mechanism that serves to pop the rear edge upwardly upon being unlocked so as to more easily allow the cover to be grasped and pivoted into its open position. The locking mechanism is accessed via a single, centrally located keyhole and may additionally be activated electronically via a remote sending unit.
The hinging mechanism includes a compound hinge positioned on each side of the cover wherein each hinge employs two links. The links are each pivotably attached to a first hinge plate that is attached to the truck bed and to a second hinge plate that is attached to the cover. The links are of unequal length and the pivot points are spaced and positioned on the brackets such that the hinge plate is forced to simultaneously move slightly upwardly and rotate while the front edge of the cover shifts slightly rearwardly as the cover is pivoted to its open position. The hinge plate that is attached to the truck is configured to be slidingly received in a pocket that is affixed to the truck. Once fully received in the pocket, a rotatable set knob positively fixes the hinge plate in place. Removal of the cover is therefore easily accomplished by simply unthreading and removing the set knob from the lifting mechanism and lifting the cover off of the truck.
The locking mechanism includes a pair of latch elements that are attached on opposite sides of the cover so as to engage a strike loop affixed to each side of the truck. A spring-loaded cam lever lifts the latching element clear of the strike loop as the mechanism is unlatched either by rotation of a key or by energization of a solenoid. Locking the cover merely requires the cover to be pushed downwardly with sufficient force to overcome the force of the cam lever and to trip the latch mechanism.
Telescoping gas struts are relied upon to assist in pivoting the cover into its open position and support the cover while in its open position. The gas struts are pivotally attached to the truck at one end and to the cover at its opposite end. The gas strut is easily detached from the truck-end pivot point while a retention clip is provided on the inside surface of the cover to capture the free end of each of the detached struts to ease the handling of cover during its removal from the truck bed. One hinge plate receiving pocket, one truck-end strut pivot and one strike loop may be attached to a single top rail bracket that extends along the top rail of the truck which in turn may be clamped to the truck rail.